Leaders of 47 nations, many of whom acknowledge they possess nuclear weapons or are thought to do so, took a step together in confronting anew the threat of mass destruction. In so doing, participants in the Nuclear Security Summit in Washington, D.C., this week made progress toward the goals of building peace and managing conflict outlined in a pastoral letter of the U.S. Catholic bishops a generation ago.

“The Challenge of Peace: God’s Promise and our Response,” stands just weeks shy of its 27th anniversary. (It’s worth a read at usccb.org/sdwp/international/TheChallenegeofPeace.pdf.) “The whole world must summon the moral courage and technical means to say no to nuclear conflict,” the letter said. Dangers remain, but the world is putting these prophetic words into action.

The bishops who wrote them would be pleased America and Russia are negotiating to reduce nuclear weapons and are working with many other nations to halt the spread of such weapons and their components.

While the letter called for a powerful international body to lead and police this work, nations are showing they can work together effectively to meet threats without sacrificing sovereignty.

One of the biggest new threats to peace in the world is the specter of a nuclear bomb possessed by international terrorist groups. They presumably would use such a device to inflict massive death and suffering for its own sake, not to achieve a political end.

Today, Russia and the U.S. retain thousands of nuclear weapons. But in a spirit of emerging cooperation on a host of international issues, they continue to take steps to reduce their nuclear stockpiles. Leaders of the two countries deserve praise for pledging a new round of arms reduction in a treaty signed last week. The Senate and the Russian parliament ought to ratify the treaty following their review.

Americans and all peace-loving peoples should support current efforts to reduce nuclear arsenals, restrict fissionable materials for such weapons and help emerging nations meet their energy and security needs without resorting to development of nuclear materials or weapons. And acting in concert, nations should continue to oppose efforts by obstinate countries or lawless terrorist groups to acquire or build such terrible weapons.

International cooperation, though halting and at times unsure, can build peace that is the hope of so many peoples. The fears of the cold war are behind while new fears of terror loom ahead. But our Lord Jesus Christ tells us not to be afraid. His wish – “peace be with you” – must be our will and the spur to our work.